A backpacker couple arrive at a village in Southern France.

At the local inn, they meet a man who offers to take them to prehistoric underground caves that are off limits for regular tourists. He shows them his bare foot which has only one toe left.

The rest, he says, are still somewhere in the caves.

The mystery of the missing toes takes the couple deep into the timeless darkness underground.

Artist Broci and author Marko Hautala will take you on a claustrophobic journey to the center of your deepest fears.